28197081 has 12 divisors (see below), whose sum is σ = 44431920. Its totient is φ = 17089080.

The previous prime is 28197061. The next prime is 28197119. The reversal of 28197081 is 18079182.

It is not a de Polignac number, because 28197081 - 2⁵ = 28197049 is a prime.

It is a super-2 number, since 2×28197081² = 1590150753841122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28197031) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 142311 + ... + 142508.

It is an arithmetic number, because the mean of its divisors is an integer number (3702660).

Almost surely, 2^28197081 is an apocalyptic number.

It is an amenable number.

28197081 is a deficient number, since it is larger than the sum of its proper divisors (16234839).

28197081 is a wasteful number, since it uses less digits than its factorization.

28197081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284836 (or 284833 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

The square root of 28197081 is about 5310.0923720779. The cubic root of 28197081 is about 304.3696773802.

The spelling of 28197081 in words is "twenty-eight million, one hundred ninety-seven thousand, eighty-one".